5. Sarah is standing 32.0 m away from Jason. If Sarah throws a snowball at a 45 degree
angle for maximum distance, what velocity must the snowball have to hit Jason directly.
(Assume Jason and Sarah are about the same height so that if she throws the snowball
from head level, it will hit Jason in the head.)

Respuesta :

Answer:

Explanation:

If air resistance is ignored and assume UP and Toward Jason are the positive directions.

horizontal analysis

d = (vx₀)t

t = d/vx₀

horizontal analysis

0 = vy₀t + ½gt²

0 = vy₀(d/vx₀)+ ½g(d/vx₀)²

as vy₀ = v₀sin45 and vx₀ = v₀cos45 and are equal.

0 = d + ½g(d²/v₀²cos²45)

-d = ½g(d²/v₀²cos²45)

-dv₀² = ½g(d²/cos²45)

   v₀² = -½g(d/cos²45)

   v₀² = -½(-9.81(32.0/cos²45)

   v₀² = 313.92

   v₀ = 17.717787...

   v₀ = 17.7 m/s